1. Field of the Invention
The present invention relates to manually controlled devices for generating multi-dimensional data for input to a microprocessor or computer. In particular, the present invention relates to a computer mouse and/or shell therefore which is normally operated with the upper extremity of the person operating the computer or microprocessor to which the device is connected, by holding and controlling the device while maintaining the upper extremity in a neutral attitude, without pronation-supination of the forearm or radial-ulnar deviation of the wrist or hand.
2. Prior Art
A computer mouse is a common device used in conjunction with a computer, for example, for multi-dimensional control of cursor movement on the screen or CRT of a monitor of a computer. A computer mouse usually includes a captured ball or sphere, a portion of which extends from the interior of the mouse. The mouse is moved over a surface, with the ball in contact with the surface so that the ball rolls over the surface defining the direction of movement of the mouse across the surface. The movement of the ball generates a two-dimensional data input for computer cursor control, which is visible on the screen or monitor of the computer. Two coordinate wheels are supported internally in the mouse which are driven by the ball as the ball rolls across the surface of a pad, for example, in accordance with the vector movement of the mouse.
A computer mouse also carries one or more buttons or switches which are operated by the person operating the mouse, for providing signals to the computer to perform one or another function, often related with the location or position of the cursor on the screen. Most computer mice currently carry one button or switch which provides a signal to the computer which is coordinated with the location of the cursor on the screen and a second button or switch which provides a signal to the computer which is independent of the cursor.
A conventional computer mouse is horizontally oriented and normally controlled by the hand and arm of an individual working on or with the computer to which the mouse is connected.
An alternative to a computer mouse is a device called a trackball. The trackball serves the same function as a mouse, relative to the computer. The trackball is essentially a stationary device with a ball mounted for full rotational movement within the mounting base. A portion of the ball is exposed so that the ball may be rotated, as desired, within its mounting, by the thumb, fingers or part of the palm of the hand, for example.
Where the mouse device is moved across a surface, for rolling the ball mounted in the mouse, across such surface, the trackball device is maintained stationary while the ball mounted in the trackball is rolled within its mounting by the thumb or fingers, for example, driving the ball. In some computer environments the devices are competitive, in other computer environments the devices are noncompetitive.
Of the two devices, the computer mouse has been designed into the "Dove Bar" mouse design, a design that is particularly suited for hand operation across the surface of a plane. The Dove Bar computer mouse is horizontally oriented and is operated normally with the hand, with the palm of the hand facing downward, over the top of the Dove Bar mouse, grasping the mouse and moving the Dove Bar mouse across the surface of a desk, for example. The Dove Bar mouse is moved by using the arm and shoulder muscles. However, when one uses the Dove Bar mouse, the forearm of the person operating the mouse is twisted into a nonneutral position, the palm or flat of the hand rotated for covering and holding the horizontally disposed Dove Bar mouse. The article "MICE VS. TRACKBALLS" by Lorraine Rice, published in PC Magazine, August 1990 edition, at pages 216-217 points out some differences between the Dove Bar design mouse and the Trackball used in conjunction with computers. The article discusses each device and describes how each is held and operated but fails to consider that, in the case of the mouse, the extremity of the person holding and/or operating the mouse is twisted into a nonneutral position, i.e., the open hand is rotated, approximating a substantially horizontal plane, with the palm of the hand facing downward. When operating the trackball, the ball of the trackball is rotated directly by finger and/or thumb manipulation. Operation of both these devices is accomplished in strained and nonneutral positions of the extremity and are overly taxing and tiresome. The present invention, an ergonomic computer mouse, overcomes this problem.